'Justifiable'

Writing in the Guardian and the Mail, Mr Dacre said Mr Miliband's speech to the Labour Party conference on 24 September had prompted the piece.

He said the paper was "deeply concerned that in 2013, after all the failures of socialism in the 20th Century, the leader of the Labour Party was announcing its return, complete with land seizures and price fixing".

Mr Dacre said the "hysteria" over the article was "symptomatic of the post-Leveson age"

The paper therefore reasoned that "the public had the right to know what influence the Labour leader's Marxist father, to whom he constantly referred in his speeches, had on his thinking", he wrote.

"The picture that emerged was of a man who gave unqualified support to Russian totalitarianism until the mid-50s, who loathed the market economy, was in favour of a workers' revolution, denigrated British traditions and institutions such as the Royal Family, the Church and the Army and was overtly dismissive of western democracy."

Mr Dacre said the headline was "controversial" but "justifiable" when read in conjunction with the article, which he said showed Ralph Miliband was "committed to smashing the institutions that make Britain distinctively British",

In his piece on Saturday, Mr Dacre said the "hysteria" that followed the original piece was "symptomatic of the post-Leveson age", and accused the BBC of "leading the charge".

"Fair-minded readers will decide themselves whether the hundreds of hours of airtime it devoted to that headline reveal a disturbing lack of journalistic proportionality and impartiality - but certainly the one-sided tone in their reporting allowed Labour to misrepresent Geoffrey Levy's article on Ralph Miliband."

'Balanced'

Former Labour spin doctor Alastair Campbell was one of the most vocal critics of the piece, but Mr Dacre attacked the BBC's decision to allow him a platform to speak.

"But the BBC's blood lust was certainly up. Impartiality flew out of the window. Ancient feuds were settled. Not to put too fine a point on things, we were right royally turned over," Mr Dacre wrote.

The BBC said in a statement: "We completely reject any suggestion that our reporting has been biased. We followed the story as it unfolded and ensured both sides had the chance to express their views.

"As a public broadcaster, we have a responsibility to report the news without fear or favour, providing balanced information and independent analysis, allowing our audiences to make up their own minds."

The Daily Mail has refused to apologise for its article, although its sister paper the Mail on Sunday did say sorry after two of its journalists went to a memorial service for the Labour leader's late uncle at which they pressed the family for reaction to the original Daily Mail article.